To say that “Phineas & Ferb” creators Dan Povenmire and Jeff “Swampy” Marsh are fans of “Star Wars” is a bit of an understatement.

“I was the first kid in line for the first showing of ‘Star Wars’ in Mobile, Ala. I watched it 19 times that summer, and more times since we were making this movie. I can’t count how many times I’ve actually seen it. But it’s pretty burned into my cerebrum,” says Povenmire.

That fervor is what the duo brought to the Disney Channel movie “Phineas and Ferb: Star Wars,” which airs at 9 p.m. Saturday. (They’ll also be offering a sneak peek of it at Comic-Con at 10 a.m. Saturday.)

The film takes place parallel to events that transpire in the original 1977 film “Star Wars: Episode IV — A New Hope.” Alongside Luke Skywalker, Han Solo, R2D2 and more, Phineas and Ferb (moisture farmers on Tatooine) are helping the rebellion in their own way — by delivering blueprints they come across (on a disc jarred loose from R2D2) on the Empire’s new Death Star.

To stay on course with the details of the story, “A New Hope” had to be screened over and over again.

“There was a lot of ‘If the boys are doing this, what is happening in “Star Wars?” ‘ So we’d have to go back and look and find which scene would intersect it. Like, it’s before this and after this; what could be happening that we could reference in the movie,” says Povenmire. “We sometimes watched it frame by frame. We even had guys counting how many laser bolts were fired as Luke and Leia swing across in the background of one of our scenes. Somebody actually figured out how many laser bolts were fired and where they hit so it would match up with our scene.”

Chewbacca, Han Solo and Isabella in a scene from “Phineas and Ferb: Star Wars.” (Disney)

“Any time we thought we weren’t quite getting the scene right, it just gave us an excuse to go back and say, ‘Hey, let’s go watch that scene again!'” says Marsh.

Some of those details are easily spotted: A “Who shot first?” line thrown in while in Mos Eisley Cantina, or listening in as Princess Leia records her message to Obi-Wan Kenobi. But those sessions also paid off with many sometimes imperceptible changes and extras thrown in to delight “Star Wars” fans.

“There’s gags in the episode that are only for the super uber geeks. Like the scene where Phineas and Ferb run into Luke Skywalker and he’s got on the hat [on Tatooine]. He looks up and sees the space battle. That was a scene that was shot for ‘Star Wars’ but cut out of the original movie. They found some scratchy footage and put in as a DVD extra,” says Povenmire.

Something not in the original movies are big musical numbers, but Phineas and Ferb have that covered. From one of the opening songs, “We Love Tatooine,” to the big party finale “Rebel Let’s Go,” songs were written to not only highlight “Star Wars” happenings, but also Phineas and Ferb’s place in that universe. Most were written by Povenmire and Marsh and their fellow writers, but some unexpected songwriting companions such as Wayne Brady lent a hand.

There was a directive, though, to keep the tones and the sounds as close to the original movie’s soundtrack as possible.

“They all had to live in the same world as the original John Williams music. We got to go over to Capitol Records and record over there with live horns and percussions and that was just a great couple of days,” says Marsh.

The drawing to the right — a poster sold by a 13-year-old Povenmire — is just one further illustration of the reverence he and Marsh have long had for “Star Wars.” In true fan fashion, the creators have tried to adhere to the “Star Wars” action formula — without straying from the fun and inventive qualities that make “Phineas and Ferb” popular.

One of the last lines of the opening scroll of the “Phineas and Ferb” movie says, “And, none of this is canon, so just relax.”

“We have changed nothing that happened in the film that you saw originally in any way,” says Marsh.

“So, sure, Agent P could’ve been the guy who stole the Death Star plans,” says Povenmire.